Plantronics CS60/CS70N/CS351N/CS361N T-piece Training Adaptor

You unplug your cordless headset from the base of the telephone phone and replace it with the Plantronics T-piece adaptor. You then plug your cordless headset into one of the Jacks on the Plantronics T-piece Adaptor and then plug in a Plantronics corded headset into the other jack.